1. Field of the Invention
The present invention relates generally to semiconductor wafer processing. More specifically, the present invention relates to an apparatus in which a semiconductor wafer can be cleaned.
2. Description of the Related Art
In the manufacture of semiconductor devices, a surface of a semiconductor wafer (“wafer” or “substrate”) must be cleaned to remove chemical and particulate contamination. If the contamination is not removed, semiconductor devices on the wafer may perform poorly or become defective. Particulate contamination generally consists of tiny bits of distinctly defined material having an affinity to adhere to the surface of the wafer. Examples of particulate contamination can include organic and inorganic residues, such as silicon dust, silica, slurry residue, polymeric residue, metal flakes, atmospheric dust, plastic particles, and silicate particles, among others.
Wafer cleaning processes are generally performed by applying a fluid to the surface of the wafer. In some instances the fluid is applied to the wafer in a sealed chamber. The method of applying the fluid to the wafer can influence the effectiveness of the wafer cleaning process. For example, a specific fluid flow pattern over the surface of the wafer may provide beneficial cleaning results. Additionally, a specific fluid pressure applied over the surface of the wafer may provide beneficial cleaning results. Traditionally, different wafer cleaning chambers have been required to obtain different fluid flow patterns and fluid pressures over the surface of the wafer. The need to have a different wafer cleaning chambers to satisfy the requirements of a variety of wafer cleaning processes can present problems with respect to overall wafer processing cost and implementation. Also, wafer cleaning processes that require the use of high fluid pressures generally require the use of large wafer cleaning chambers to withstand the high pressure. Larger wafer cleaning chambers correspond to increased overall wafer processing cost.
In view of the foregoing, there is a need for a wafer cleaning chamber that allows for variable control of fluid pressures and fluid flow patterns as required to meet the needs of different wafer cleaning processes. The wafer cleaning chamber should also be able to accommodate wafers of different sizes. Furthermore, the wafer cleaning chamber should combine an ability to contain high pressures with an overall minimum size.